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species was and continues to be Bromus inermis for all years sampled. Four plant <br />species (Agropyrnn smithii, Bromus inermis, Poa pratensis, and Conwlvulus arvensis) <br />were found to be dominant or major components of each community during all years <br />sampled. Two species, Bromus inermis and Convolvulus arrt?nsis are present in both <br />the dry meadow reference area and the historic record vegetation community in <br />approximately the same relative percentages over the years sampled. Relative cover of <br />plant species in the sampled communities correlated well with the amount of "pre- <br />growing season" precipitation received. <br />Herbaceous production in the communities sampled showed a general correlation with <br />"pre-growing season" precipitation. In the historic record vegetation community, <br />precipitation increased 43.3 percent between 1996 and 1997, and herbaceous <br />production increased 44.8 percent during the same period. Interestingly, the same <br />correlation cannot be made for the 1982 and 1995 dry meadow reference area. The <br />increase in "pre-growing season" precipitation amounts between 1982 and 1995 was <br />24.6 percent, yet herbaceous production dropped 5.3 percent. This does not represent <br />the generally observed relationship, and it is hypothesized that this anomalous <br />observation is related to sampling technique differences. <br />Table 7 provides a comparison of species numbers from three herbaceous communities <br />at the West Elk Mine. In 1982, a "normal" precipitation year, total species numbers at <br />the dry meadow vegetation community and the dry meadow reference area were 13 and <br />15 respectively. In L995, a wet year with 14,23 inches of "pre-growing season" <br />precipitation, species numbers at the dry meadow reference area increased to 2l. <br />Species numbers were the lowest (siz) in the historic record vegetation community in <br />1996, corcesponding with a yeaz with "pre-growing season" precipitation 32 percent <br />below the mean. With increased precipitation in 1997, the historic record vegetation _, <br />community rebounded in species numbers to l5, equivalent in value to species numbers <br />from the dry meadow community and dry meadow reference area in the "normal" <br />precipitation yeaz of 1982. As was observed in 1996 and 1997 in the historic record <br />vegetation community, numbers of fort species increased greatly in the wet year 1995 <br />at the dry meadow reference area when compared to the normal precipitation year of <br />1982. It is deduced that with increased precipitation prior to the growing season, <br />numerous opportunistic cool season species germinate, flower, and reproduce during <br />the favorable normal and wet years, while remaining dormant during the unfavorable <br />dry years. Presumably, this relates to their ability to compete with the dominant and <br />more aggressive graminoids during unfavorable conditions. <br />Figure 4 depicts the relationship between total vegetation cover and total herbaceous <br />production and "pre-growing season" precipitation in the historic record vegetation <br />community (HANG), the dry meadow community (DM) and the dry meadow reference <br />area (DMRA). The four years of data from the three communities illustrate distinct <br />relationships directly related to"pre-growing season "precipitation. <br />-11- <br />